1. Field of the Invention
This invention relates to surgical saws, and in particular to a dual bladed surgical saw and method of use.
2. Background of the Invention
Certain surgical procedures require bone cuts at precise angles. For example, the most common bunion surgical procedure is the Austin bunionectomy, also known as the Chevron bunionectomy.
The Austin bunionectomy procedure requires cutting a sixty degree angled cut into the first metatarsal head. The two resultant sections of the first metatarsal head are translated sideways, and then fixated. Fixation may be accomplished with a K-wire, pin, or other appropriate fixation device. Protruding sections of bone are cut off as appropriate, and a wedge may be removed from the first phalange as necessary. After the bones involved are aligned properly, they may be fixated with pins, screws, staples, etc., as appropriate.
The optimal angle at which to make the Austin bunionectomy angle cut is sixty degrees, that is to say, two cuts disposed at sixty degrees to each other. More than sixty degrees results in a loss of stability, while with less than sixty degrees one gets into the spike area, and healing surface area is sacrificed. Therefore it is important to achieve a sixty degree bone cut for best results from the procedure.
Existing Designs.
Currently, a first cut is made, and then a guide, which could be a guide wire, is used to make the second cut. This procedure is less than ideal, because it is time-consuming and not extremely accurate. Thus, it would be desirable to provide a dual bladed surgical saw whose two blades simultaneously make a pair of cuts at sixty degrees relative to each other. This ability would improve efficientcy as well as accuracy.
Further, it would be desirable to be able to vary the angle between the two blades, in order to make other bone cuts necessary during surgery. For instance, it would be helpful to be able to make two bone cuts simultaneously to isolate a bone wedge for removal. Such cuts typically require a pair of bone cuts at an angle of ten to thirty degrees relative to each other.
Other angled bone cuts which would benefit from a dual bladed surgical saw include hand procedures. It would be beneficial to provide a dual bladed surgical saw whose blades could be pre-set to the correct angle for the procedure, and then both cuts made simultaneously and independently by the two blades at precisely the correct angle.
It would also be desirable to be able to remove one blade from the dual bladed surgical saw to leave only one blade. This blade could be used conventionally for cuts where only one blade is required.
A number of dual bladed surgical saws have been proposed. U.S. Pat. Nos. 7,744,616 and 6,007,541, Publication No. 2011/0230887, and Statutory Invention Registration H571 by O'Donoghue, Scott, Bickenbach, and Hollinger et al. respectively, all described saws having two blades. These designs all taught two parallel blades, with no provision for changing the angle between them. Thus, these would not be able to make the sixty degree cuts required during Austin bunionectomies, nor the ten to thirty degree angled cuts required for bone wedge removal, nor the other angled cuts required by other procedures.
U.S. Pat. No. 6,860,886 was granted Lee for a reciprocating surgical saw having a single blade whose angle relative to the handle was adjustable. While this design disclosed angular adjustability of the single blade, it did not disclose a single saw having two blades, nor adjustability of the angle between the two blades. Thus, the Lee device would not serve to make the sixty degree cuts required during Austin bunionectomies, nor the ten to thirty degree angled cuts required for bone wedge removal, nor the other angled cuts required by other procedures.